Finite-Time Dynamic Sliding Mode Control for Non-Minimum Phase Hypersonic Vehicle

A sliding mode control (SMC) strategy based on Byrnes-isidori (B-I) normal form is proposed to solve the tracking control problem of non-minimum phase (NMP) hypersonic flight vehicle (HFV) under external disturbance (ED). A nonlinear disturbance observer (NDO) is used for ED, the estimation error is guaranteed to be bounded stable. A dynamic sliding mode controller is constructed to stabilize internal dynamics, and a dynamic inverse controller is designed to stabilize the external dynamics. Aiming at stabilizing the velocity subsystem, a sliding mode controller is designed. Asymptotic stability of internal dynamics, practical finite time stability of velocity tracking error and bounded stability of external dynamic are proved by Lyapunov theory. Simulation is used to verify the effectiveness of the control strategy.